A little more than three years ago, Wayne Swan, Australia's then Deputy Prime Minister unexpectedly gave the $72 million reconstruction project the green light, following some ambitious lobbying by former Brisbane City councillor David Hinchliffe.

But as is so often the reality of the political cycle, the pair is not on the official guest list for Sunday's opening event.

"I've been thinking lately the key people involved are never there to see the results of their decisions," Mr Hinchliffe said.

"But that's politics."

When floodwaters submerged Brisbane in January 2011, the original floating walkway was one of the city's many infrastructure casualties, yet, despite its enormous popularity, in the wake of the disaster public opinion was divided over replacing it.

Reconstruction talks put a price tag in excess of $60 million on the project, which many people deemed too excessive, and then-Lord Mayor Campbell Newman ruled out ratepayers funding the rebuild.

As non-essential infrastructure, it did not technically qualify for federal flood recovery money.

Riverwalk was, Mr Hinchliffe said, at risk of becoming nothing more than a "fond memory".

"I went to Wayne Swan pleading to get federal support but we thought we had Buckley's chance of getting Riverwalk back," he said.

"$72 million is a huge ask when it's not a major piece of road or public transport infrastructure, so to be able to get that commitment was a manna from heaven.

"But it would never have been done if Wayne Swan hadn't broken the rules."

The "rules" Mr Swan broke were more of a bending of requirements for flood recovery funding qualification.

Mr Swan, whose political existence these days is somewhat quieter in opposition as simply the Member for Lilley, said though Riverwalk was not technically essential infrastructure, he and the-then Federal Minister for Queensland Flood Recovery, Joe Ludwig, deemed it valuable infrastructure in other ways.

"It didn't come into the terms of the agreement being non-essential but we thought it had become an essential part of the fabric of the place," he said.

"If we didn't bite the bullet, it wouldn't be here, it would have been one of those things that fell by the wayside."

The funding agreement spanned three levels of government, with the Commonwealth contributing $54 million, the State $18 million and Brisbane City Council overseeing construction, as well as assuming responsibility for ongoing maintenance.

Mr Swan said while there had been plenty of criticism of the project cost, as well as political point scoring, in the end, the people of Brisbane had a brand new asset to enjoy.

"It was considered extravagant and it turned out to be very expensive and smaller minded people wouldn't have taken the decision to do this," he said.

"It was regrettable at the time there was a lot of politics played but at the end of the day we got the right outcome for the city and that's the most important thing."

The new, permanent structure, unlike its floating predecessor, has been designed to one-in-2000 year flood resilience.

A spokesman for Premier Campbell Newman said he would not attend the official opening on Sunday.

"The State Government is proud to be putting $18 million towards rebuilding Brisbane's iconic Riverwalk which will be enjoyed by Queensland families and visitors for years to come," the spokesman said.

"State Member for Brisbane Central Robert Cavallucci will be representing the State Government at Sunday's event."

Though neither Mr Swan nor Mr Hinchliffe are among the invited dignitaries, both are eager to join other Brisbane residents to be among the first to test out the new structure.

"I'm pretty happy to see it open and really, it might be located here but it's a valuable piece of citywide infrastructure," Mr Swan said.